real time Clock Chip not found Pearl 2008

Hello, I am repairing an Avolites Pearl 2008 Moving, serial number STY009025. -System mode: Pearl 2008 V3.0.2 Jun 01 2006 when I want to set the time I get the following message: "real time Clock Chip not found - Please contact AVOLITES - hit EXIT to continue" Can you tell me how to proceed? I would like to update it Where I can find the eproms Is there a kit for a USB card? if attached some pictures Thank you Arnaud MARTRE